# OpenSeaMap vs SeaNav

The clearest difference is rating: SeaNav at 4.4 against OpenSeaMap's 1.0. SeaNav also leads on ratings volume (247 vs 1) and review sentiment (55% vs 38%). On price, ads, in-app purchases and monetization model there is nothing between them.

Both are free to download. OpenSeaMap sells 1 one-off in-app purchase and SeaNav sells 18 in-app purchases, starting at $4.99 per year. Whichever you choose, the download price is not the number that matters.

SeaNav holds the better App Store score, 4.4 against 1.0. That said, the two scores are not equally well evidenced: SeaNav has 247 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 38% of OpenSeaMap's written reviews are positive against 55% of SeaNav's.

OpenSeaMap ships an update every 2 months, SeaNav every 3 weeks. Both last shipped on October 21, 2026.

## The numbers

| Metric | OpenSeaMap | SeaNav |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [1.0 (1 ratings)](https://appshunter.io/ios/app/openseamap/id495210783/reviews) | **[4.4 (247 ratings)](https://appshunter.io/ios/app/seanav/id857841271/reviews)** |
| Number of ratings | 1 | **247** |
| Positive reviews | 38.3% of reviews | **54.7% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 3 weeks** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 13 MB | 159 MB |
| Requires iOS | 18.6 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod, Apple Watch** |
| Age rating | 4+ | 4+ |
| Developer | [appdoctors UG](https://appshunter.io/developer/961029450) | [Pocket Mariner Ltd.](https://appshunter.io/developer/719592131) |

## What reviewers say

### OpenSeaMap

[App page](https://appshunter.io/ios/app/openseamap/id495210783)

This app provides a free, worldwide nautical chart with detailed sea information, including lights, weather data, and harbor details. It offers chartplotting, waypoint management, and offline map caching for navigation. Users can mark locations, enter coordinates, and adjust chart zoom for optimal viewing.

**Highlights:** Free worldwide sea chart, Chartplotting with tracking, Waypoint creation and export, Offline map caching, Mark and search locations, Adjustable chart zoom

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| OpenSeaMap Professional | $1.99 | one-time |


### SeaNav

[App page](https://appshunter.io/ios/app/seanav/id857841271)

This app provides high-resolution marine charts, route planning, and real-time navigation for boaters. It offers features like AIS ship tracking, tide and weather information, and offline chart access. Advanced capabilities include augmented reality views and autopilot integration.

**Highlights:** High-resolution marine charts, Autoroute planning, Real-time GPS navigation, AIS ship tracking, Tides and weather, Offline chart access, Augmented Reality View

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases (18)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weather charts | $4.99 | per year |
| New Zealand Charts | $5.99 | per year |
| NOAA US Raster Charts | $9.99 | per year |
| US Charts | $9.99 | per month |
| Pro Features | $10.49 | per year |
| Bermuda and BVI Charts | $12.99 | per year |
| Italy, Sardinia and Sicily | $17.99 | per year |
| Norwegian Charts | $18.49 | per year |
| US Charts | $19.99 | per year |
| Portuguese Charts | $19.99 | per year |
| BE & NL Charts | $20.99 | per year |
| Spanish Charts | $24.99 | per year |
| UK & IE Charts | $24.99 | per year |
| French Charts | $24.99 | per year |
| Canadian Charts | $26.99 | per year |
| Croatian Charts | $28.49 | per year |
| Man Overboard & Anchor Watch | $4.99 | one-time |
| Pro Features | $14.99 | one-time |

**What reviewers like**

- 👍 Easy to use and great price
- 👍 Much easier to use than competitors
- 👍 UKHO Charts at a reasonable price
- 👍 Intuitive interface, clear and uncluttered
- 👍 Supports NMEA data integration

**What reviewers complain about**

- 🐛 Frozen/locked app
- 💰 Neil and dime for everything
- ❌ Not picking up vessels or ship traffic
- ❌ Charts not good, weather not working
- ❌ Difficult to download and update charts

**Reported bugs**

- Frozen/locked app
- Not picking up vessels or ship traffic
- App does not open
- Crashes after crashes
- Sailing mode crash

**Requested features**

- Can you see water depth on Apple Watch?
- Download all purchased charts button
- Update all purchased charts button
- Legend for symbols and colors
- Brief chart reading explainer


## Frequently asked questions

### Is OpenSeaMap free?

OpenSeaMap is free to download, with in-app purchases available.

### Is SeaNav free?

SeaNav is free to download, with in-app purchases available.

### Which has better reviews, OpenSeaMap or SeaNav?

SeaNav is rated higher. OpenSeaMap averages 1.0 out of 5 from 1 ratings, while SeaNav averages 4.4 from 247 ratings.

### Do OpenSeaMap or SeaNav have ads?

Neither OpenSeaMap nor SeaNav shows ads.

### Which is updated more often, OpenSeaMap or SeaNav?

OpenSeaMap ships an update every 2 months, and SeaNav every 3 weeks. Most recently, OpenSeaMap was updated on October 21, 2026 and SeaNav on October 21, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*